US Patent 7329313 Air cleaner

An air cleaner includes a housing, a filter, a photocatalyst reaction unit which can form spiral a air flow, a forced convection device, and an electrocircuit controller. The forced convection device is located between the filter and the photocatalyst reaction unit. Because the air cleaner uses a longitudinal air conduit, an air inlet along a tangential direction of the air conduit and spiral guide vanes at the inlet, air passing through a fan and into the air conduit flows spirally in the conduct conduit to increase the time during which air contacts the photocatalyst and enables the light of the ultraviolet lamp to radiate the photocatalyst directly so that the cleaning efficiency of the photocatalyst is increased.